1. Field
Embodiments relate to an image sensor, a substrate for the same, an image sensing device including the image sensor, and associated methods.
2. Description of the Related Art
An image sensor may be formed as a “front side” CMOS image sensor that includes a plurality of photo diodes in a substrate. After forming the photo diodes, metal wiring patterns may be formed on the photo diodes. The metal wiring patterns may be formed to provide apertures for the photo diodes to receive external light. However, light entering the apertures at an angle may be reflected by the metal wiring patterns. Further, an interlayer dielectric layer surrounding the metal wiring patterns may absorb light incident thereon. Thus, the amount of light reaching the photo diodes through the apertures may be reduced, resulting in poor device sensitivity. Further, light reflected within the image sensor may impinge upon adjacent photo diodes, such that cross-talk between photo diodes occurs. An alternative to the front side image sensor is a back side image sensor. However, current back side image sensor designs and manufacturing processes may suffer from drawbacks such as dark current, lack of light sensitivity, i.e., poor quantum efficiency, and the need to protect heat sensitive structures during manufacturing.